The removal of surface layers from liquids

ABSTRACT

A device for pumping away floating oil slicks comprises a floating inlet chamber. Oil is drawn through an upper wall of the chamber and is pumped upwardly from the lower part of the chamber. Two embodiments are described one of which includes an outlet part connected to the chamber by parts which can straddle a boom confining the oil and the other of which includes a circular chamber supported by a long dependent pipe.

I United States Patent 11 1 1111 3,759,390

McCombie [4 1 Sept. 18, 1973 [54] THE REMOVAL OF SURFACE LAYERS 3,642,140 2/1972 Parker 210/242 FROM LIQUIDS 1,107,391 8/1914 Welch 210/242 [75] Inventor: Frederick Walter McCombie, EIGN PATENTS OR APPLICATIONS London, England 804,368 11/1958 Great Britain... 210 242 [7 3] Assignee: Megator Pumpsand Compressors OTHER PUBLICATIONS Englmd Auslegeschrift 1,064,367, Veld, Aug. 27, 1959. [22] Filed: Feb. 10, 1971 [2]] Appl No 114,157 Primary Examiner-Samih N. Zahama Assistant ExaminerT. A. Granger Att0rneyA'rthur B. Colvin [30] Foreign Application Priority Data Mar. 5, Gf3l Aug. 26, 1970 Great Britain 41,,089/70 A devlce for pumping away floating 011 slicks comprises 52 11.5. C1. 210/242, 210/010. 21 a floating inlet chamber Oil is drawn through an pp [51] Int. Cl E021) 15/04 wan 0f the chamber and is Pumped upwardly from the 5s 1 Field 61 Search... 210/169, 242, DIG. 21 lower p of the chamber- TWO embodiments are scribed one of which includes an outlet part connected [56] References Cited to the chamber by parts which can straddle a boom UNITED. STATES PATENTS confining the oil and the other of which includes a circular chamber supported by a long dependent pipe. 1,644,248 10/1927 Goldman 210/242 2,608,300 8/1952 Small 210/D1G. 21 3 Claims, 4 Drawing Figures PAIENTEUSEPI mm 1 SHEET 1 0F 3 imam/ale M/fis/a mo, LIE

I INVENTOR [as M fldh ATTORNEY The invention relates to the removal of surface layers from liquids and is particularly concerned with the removal of slicks of oil or similar undesirable material floating on water. I

It is an object of the present invention to provide ap-' paratus which can remove the surface layer unaccompanied by, or accompanied by a very small amount of, the liquid on which the surface layer floats.

According to the present invention there is provided an apparatus for removing a surface layer from a liquid, such apparatus comprising a chamber capable of floating in the liquid, inlet means at an upper surface of the chamber through which the surface layer can enter the interior of the chamber and outlet means through which liquid can be drawn upwardly from the lower part of the. chamber to a source of suction.

The phrase capable of floating means that the chamber is inherently buoyant or is rendered buoyant by an additional element or elements.

The invention will now be described by way of example and with reference to the accompanying drawings, wherein: FIG. 1 is a perspective view of an apparatus in accordance with a first embodiment of the invention;

FIG. 2 is a section on the line 1111 of FIG. 1;

FIG. 3 is a section on the line 11l-l11 of FIG. 1; and

FIG. 4 is a side view partly in section of an apparatus in accordance with a second embodiment of the invention.

The apparatus shown in FIG. 1 of the drawings comprises front and rear laterally extending elongate parts 1 and 2 respectively. The parts 1 and 2 are of equal length and disposed the one behind the other in parallel The rear part 2 hereinafter referred to as the outlet part, comprises a generally cylindrical transverse tubular .element 16 having a centrally disposed rearwardly extending spigot, manifold or elbow 17 for connection to a suction. hose leading to an appropriate pump. A connecting and bridging pipe assembly 3 extends from each end of the element 16 to the corresponding part of the chamber 5. Each pipe assembly comprises front and rear vertical parts 18 and 19 and an intermediate part 20 of inverted V form. Struts 21 extend laterally outwardly from the rear vertical part 19 and a spindle 22 extends vertically between the outer ends of the struts 21. A cylindrical float 4 is slidably received on each spindle 22 and is settable by a grub screw 23. A horizontal rail 24 extends between the upper parts of the vertical parts 18 and 19 of each pipe assembly 3. A weight 25 is slidable in the rail to adjust the trim of the apparatus and is settable by a grub screw 26.

The use of the apparatusto remove an oil slick floating on water and contained by a boom will now be described by way of example. .The operator can manipulate the apparatus by grasping the pipe assemblies while standing on the clean side of the boom. The inlet part 1 floats in the water carrying the slick and the outlet part 2 floats in clean water the pipe assemblies 3 bridging the boom. The buoyancy and trim of the apparatus are so contrived, if necessary by adjustment of the floats 4 and the weights 25 that, in the normal floating position with the pipes or the assemblies 3, which define balancing chambers, empty, the weirs 7 are just clear of the surface of the slick. The inlet part 1 is then slightly depressed so that oil is drawn over the weirs 7 through the strainer plate 8 into the interior of the relationshipvTwo identical bridging assemblies 3, parallel when viewedin plan, extend longitudinally to connect the parts 1 and 2m that the apparatus is generally rectangular when viewed in plan; Cylindrical floats .4

apparatus measures 1% metres by 1 metre.

The front elongate part 1, hereinafter referred to as the inlet part, comprises an elongate chamber 5 of gen erally rectangular cross-section. As can well be seen in FIG. 3 of the drawings the chamber 5 comprises a body 6 of rectangular channel section having the upper end parts of the flanges outwardly and upwardly inclined to provide elongate strips constituting splitter weirs 7. A

removable lid for the chamber 5 is constituted by an.

elongate rectangular perforated strainer plate 8 having the longitudinal edge parts 9 downturned to fit the spindle 13 extends between the outwardly projecting flanges 14 of the bracket 12. Afloat 4 is slidably received on each spindle l3 and is settable to the required vertical positionby a grub screw 15.

v are provided at the corners of the apparatus. A typical chamber 5. The liquid can be observed flowing over-the weir and to assist this observation. the weir is advantageously constructed from stainless steel or other bright material. Oil in the chamber is pumped through the pipes 18 to the element 16 and away through the suction hose. The extension of the pipes 18 into the lower part of the chamber 5 is advantageous for the following reasons: I n

The pump has an approximately uniform displacement of eitherliquid or air and this is set at a rate at whichthe oil can come overthe weirs 7 with an operating head approximately equal to the thickness of the oil layer. If, due to ripples or other disturbance for example, the amount coming over the weir is less than the pump capacity, the lower ends of the pipe remain submerged in liquid. The level of the liquid in the chamber Sin these circumstances goes down but normally'the necessary amount of liquid again comes over the weirs before air is drawn into the pipes. In operation with the pipes of the assemblies 3 full of liquid the buoyancy of the apparatus is such that the weight of liquid causes the inlet part .1 to be maintained in. the correct position with the weirs 7 just below the surface of the liquid in the slick. The inverted V-shape of the intermediate parts 20 assists the correct trim of the apparatus as they tend to be either full of liquid or full of air. A horizontal cross-piece would have anindeterminate amount of liquid going along itslower portion while the upper portion would contain air.

When all the oil has been removed the inlet part 1 is raised so that air is drawn in and the pipes are emptied of liquid. The chamber then floats with the weirs 7 above the liquid surface and pumping of liquid ceases until the inlet part is again depressed. Variations in the submergence of the outlet part 2 such as might result from the pull of the hose will merely cause the elongate and narrow chamber to turn slightly in a plane perpendicular to its length and will have little effect on the submergence of the weirs. The generally square configuration of the apparatus with floats 4 at each corner gives maximum resistance to anytwisting effect resulting from the weight or pull of the hose. In another embodiment envisaged the apparatus is in the form of a regular trapezium, the parts 1 and 2 being parallel but the outlet part 2 being longer than the inlet part 1. The pipe assemblies 3 are forwardly convergent. The chamber 5 is in a central position so that any twisting of the apparatus causes only small variations in the submergence of the weirs 7.

Referring now to FIG. 4 of the drawings the second embodiment of the invention shown therein is circular when viewed in plan. An inlet chamber 27 is of shallow dished shape incorporating a rim 28 constituting a splitter weir. A generally cylindrical float 29, formed for example for filling the'lower part-of'the chamber with closed-cell plastics foam, supports the chamber 27. A disc shaped strainer 30 covers the chamber27'. A suction pipe 31, defining a balancing chamber, extends from a position adjacent the base of the chamber 27 and has an elbow.32 at the upper part thereof connected to a. suction hose 33. The suction pipe and elbow 32 provide a handle for the apparatus. The apparatus again floats so that the weir 28 is above or below the surface of the liquid according to whether the pipe is full of air or liquid.'

I claim:

1. An apparatus for removing a surface layer from a liquid, such apparatus comprising a chamber capable of floating in the liquid, inlet means at an upper surface of the chamber through which the surface layer can enter the interior of the chamber, structure on the inlet means defining a peripheral edge of the chamber over which the surface layer flows into the chamber, outlet means defining a balancing chamber, through which liquid can be drawn upwardly from the lower part of the chamber to a source of suction, said outlet means comprising at least one pipe leading upwardly from the inlet chamber and then downwardly substantially in .the form of an inverted V of sufiicient width to straddle any boom or interceptor employed to contain the oil, the downward ends being connected to a floating manifold or elbow from which a hose connects to the source of suction, and flotation means such that the apparatus floats with the inlet means to the chamber above the surface of the liquid when the outlet means contain little or no liquid and below the surface when the outlet means are substantially filled with liquid.

2. An apparatus as claimed in claim 1 in which the chamber is of narrow rectangular shape with thelong sides forming the entry edges perpendicular to the plane of the inverted V suction pipes, so that-any tilting of the apparatus resulting'from variations in the submergence of the manifold or elbow due to the drag of a suction hose or to varying quantities of liquid in' the manifold and hose have a minimal effect on the submergence and trim of the chamber.

3. An apparatus as claimed in claim '1, in which the front and rear portions of the V shaped pipe is connected by a horizontal member carrying a sliding weightby means of which the submergence and trim of the chamber can be adjusted. 

1. An apparatus for removing a surface layer from a liquid, such apparatus comprising a chamber capable of floating in the liquid, inlet means at an upper surface of the chamber through which the surface layer can enter the interior of the chamber, structure on the inlet means defining a peripheral edge of the chamber over which the surface layer flows into the chamber, outlet means defining a balancing chamber, through which liquid can be drawn upwardly from the lower part of the chamber to a source of suction, said outlet means comprising at least one pipe leading upwardly from the inlet chamber and then downwardly substantially in the form of an inverted V of sufficient width to straddle any boom or interceptor employed to contain the oil, the downward ends being connected to a floating manifold or elbow from which a hose connects to the source of suction, and flotation means such that the apparatus floats with the inlet means to the chamber above the surface of the liquid when the outlet means contain little or no liquid and below the surface when the outlet means are substantially filled with liquid.
 2. An apparatus as claimed in claim 1 in which the chamber is of narrow rectangular shape with the long sides forming the entry edges perpendicular to the plane of the inverted - V suction pipes, so that any tilting of the apparatus resulting from variations in the submergence of the manifold or elbow due to the drag of a suction hose or to varying quantities of liquid in the manifold and hose have a minimal effect on the submergence and trim of the chamber.
 3. An apparatus as claimed in claim 1, in which the front and rear portions of the V shaped pipe is connected by a horizontal member carrying a sliding weight by means of which the submergence and trim of the chamber can be adjusted. 